R/Grashof.R

#' @export#' Grashof<-function(L=1, Ts=25, Ta=20){# Grashof number# Source: Blaxter, K. 1989. Energy Metabolism in Animals and Man.# Gr=agL^3(Ts-Ta)/v^2# L is the characteristic dimension, usually the vertical dimension. For reference, # a cylinder's characteristic L would be its height, assuming it is standing on its end# Units of L should be in metres# This L should be the same L as is used for the convective coefficient calculation# Ts is the surface temperature# Ta is the ambient temperature# v2 is the kinematic viscosity squared
a<-1/273# (coefficient of thermal expansion of air)
g<-9.81# acceleration due to gravity (Units: m/s2)
v<-airviscosity(Ta)
Gr<-a*g*L^3*(Ts-Ta)/v^2
Gr
}